We propose to continue our collaborative study of melanoma risk factors in women. We hypothesize that some of the risk factors for breast cancer also may influence women's risk of melanoma. In the initial grant period, we found evidence of a reduced risk of melanoma associated with higher parity and earlier age at first birth. We propose to extend our investigation to two other hormone-related factors associated with breast cancer risk -- body weight and alcohol use. Recent results also indicate an excess melanoma risk among current or recent oral contraceptive users. To provide a more detailed analysis of the effects of oral contraceptives, we will add data from two large case-control studies completed since our study began. Additionally, we will systematically examine whether artificial tanning devices, used by an increasing number of women worldwide, affect risk of melanoma. We will perform a standard set of analyses on data collected on over 6,500 women (about 3,000 melanoma cases and over 3,500 controls). The proposed work will encompass the largest group to date of women melanoma case and control subjects who have had risk factor information collected through personal interviews. Therefore, we will be able to explore hypotheses that have not been previously considered and could not be fully addressed in a single study. Our findings will help identify the factors that place women at greatest risk for melanoma and ultimately aid the prevention of these malignancies.